1. Field of the Invention
This invention relates to the construction of raw-edge, variable power transmission V-belts with the width of the top surface thereof being greater than the height thereof.
2. Description of the Background Art
V-belts require high resistance to lateral pressure since they transmit power to the cooperating pulleys by a "wedge effect". Particularly high resistance to lateral pressure is required where the V-belt has a wide top surface. Various attempts have been made in the prior art to enchance the lateral pressure resistance. Such attempts have been directed to reinforcing the portion of the belt under the compression section.
Illustratively, one such prior art belt was constructed with a plurality of short fibers embedded in transverse orientation between the load-carrying section and the reinforcing member under the compression section. Such belts, however, were found to be unsatisfactory in that wear and cracking of the compression section occurred due to friction with the pulley. Further, such belts were subject to peeling separation of the tension cords and compression section due to stresses concentrated in the portion under the compression section during belt inflection. Further, when used with small diameter pulleys, such belts were found to be less inflective, and the portion under the compression section was significantly heated causing degradation of the compression section.
Another attempt to provide improved lateral pressure resistance and inflective characteristics is illustrated in Japanese Utility Model Publication No. 1977-20623. As disclosed therein, the V-belt is arranged with cogs in the bottom portion thereof. Fabrics are embedded in the cogged area, the fabrics being impregnated with natural fiber, rubber, synthetic resin, or the like. Although such a cogged V-belt provides some improved resistance to lateral pressure due to the embedment therein of said fabrics, such belts have been found to be too hard and inflexible for long trouble-free life.